Syrian People's Protection Units (YPG) on a tank in frontline of Raqqa fights against Daesh, on January 1, 2016. (Photo by Jacob Simkin/NurPhoto via Getty Images)
Syrian People's Protection Units (YPG) on a tank in frontline of Raqqa fights against Daesh, on January 1, 2016. (Photo by Jacob Simkin/NurPhoto via Getty Images)